Intensive Care Medicine

, Volume 34, Issue 11, pp 2026–2034

Proportional assist ventilation with load-adjustable gain factors in critically ill patients: comparison with pressure support

  • Nektaria Xirouchaki
  • Eumorfia Kondili
  • Katerina Vaporidi
  • George Xirouchakis
  • Maria Klimathianaki
  • George Gavriilidis
  • Evi Alexandopoulou
  • Maria Plataki
  • Christina Alexopoulou
  • Dimitris Georgopoulos
Original

DOI: 10.1007/s00134-008-1209-2

Cite this article as:
Xirouchaki, N., Kondili, E., Vaporidi, K. et al. Intensive Care Med (2008) 34: 2026. doi:10.1007/s00134-008-1209-2

Abstract

Objectives

It is not known if proportional assist ventilation with load-adjustable gain factors (PAV+) may be used as a mode of support in critically ill patients. The aim of this study was to examine the effectiveness of sustained use of PAV+ in critically ill patients and compare it with pressure support ventilation (PS).

Design and setting

Randomized study in the intensive care unit of a university hospital.

Methods

A total of 208 critically ill patients mechanically ventilated on controlled modes for at least 36 h and meeting certain criteria were randomized to receive either PS (n = 100) or PAV+ (n = 108). Specific written algorithms were used to adjust the ventilator settings in each mode. PAV+ or PS was continued for 48 h unless the patients met pre-defined criteria either for switching to controlled modes (failure criteria) or for breathing without ventilator assistance.

Results

Failure rate was significantly lower in PAV+ than that in PS (11.1 vs. 22.0%, P = 0.040, OR 0.443, 95% CI 0.206–0.952). The proportion of patients exhibiting major patient–ventilator dyssynchronies at least during one occasion and after adjusting the initial ventilator settings, was significantly lower in PAV+ than in PS (5.6 vs. 29.0%, P < 0.001, OR 0.1, 95% CI 0.06–0.4). The proportion of patients meeting criteria for unassisted breathing did not differ between modes.

Conclusions

PAV+ may be used as a useful mode of support in critically ill patients. Compared to PS, PAV+ increases the probability of remaining on spontaneous breathing, while it considerably reduces the incidence of patient–ventilator asynchronies.

Keywords

Controlled modesAssisted modesPatient–ventilator interaction

Supplementary material

134_2008_1209_MOESM1_ESM.doc (524 kb)
ESM1 (DOC 524 kb)

Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Nektaria Xirouchaki
    • 1
  • Eumorfia Kondili
    • 1
  • Katerina Vaporidi
    • 1
  • George Xirouchakis
    • 1
  • Maria Klimathianaki
    • 1
  • George Gavriilidis
    • 1
  • Evi Alexandopoulou
    • 1
  • Maria Plataki
    • 1
  • Christina Alexopoulou
    • 1
  • Dimitris Georgopoulos
    • 1
  1. 1.Intensive Care Medicine Department, University Hospital of Heraklion, Medical SchoolUniversity of CreteCreteGreece